Heed Stroke's Warning Signs

by Food and Drug Administration (FDA)

(Page 2 of 2)

Turning the Tide

While strokes like McGarry's continue to cause devastating effects, new treatments now offer the potential for reversing or lessening stroke effects. The conclusion of a December 1996 symposium sponsored by NINDS that brought together experts from medical centers nationwide was that stroke is always a medical emergency. To survive or recover from it requires immediate care and effective responses from everyone in the "chain of care": medical technicians, emergency departments, and doctors. Public education also is crucial so stroke victims and those around them will recognize stroke symptoms and seek help quickly.

Before 1995, the medical community viewed stroke mainly as an "unfortunate medical problem requiring only supportive care and monitoring," writes Paul E. Pepe, M.D., of Pittsburgh's Allegheny General Hospital, in an overview of the NINDS symposium. Unless a patient had passed out or was having trouble breathing, the case often was not handled urgently.

Now the stroke-care landscape is changing — albeit slowly — as more emergency rooms adopt policies of treating appropriate stroke patients with the bioengineered clot-dissolving drug Activase. In a dramatic five-year clinical trial sponsored by the National Institutes of Health and concluded in 1995, 624 patients received either intravenous Activase or a placebo within three hours of stroke symptoms' onset. The result was that 11 percent more of the Activase-treated patients had few or no signs of disability compared to the placebo group.

"One of the keys to the success of [the NIH study] was treating stroke as the true emergency that it is," says Thomas Brott, M.D., clinical investigator at the University of Cincinnati Medical Center, one of the study sites. "The concept that stroke is every bit as serious as heart attack is one that physicians must recognize in order for this new treatment to have widespread benefit."

Activase is indicated only for treating ischemic strokes. So before the drug is used, medical professionals must rule out hemorrhagic stroke by various tests, including a computerized axial tomography (CT) scan, which can indicate hemorrhages through sectional views of the brain.

Despite Activase's promise, it has been slow to catch on as a stroke treatment. In a November 1997 American Heart Association conference, researchers presented findings estimating that of 200,000 stroke patients who might have benefited from the drug, only 6,000 received it. Though some of these patients reached the emergency room too late to get the drug, others were not treated because emergency personnel were not trained or prepared to administer it, the researchers say.

Another drug, Coumadin (warfarin), can cut in half the 80,000 strokes that occur each year due to the rapid and erratic heartbeat condition called atrial fibrillation. But it too is underused, according to a study by the Agency for Health Care Policy and Research (AHCPR). Atrial fibrillation makes people more prone to form blood clots in the heart that can lodge in the brain and cause strokes. Though Coumadin can thin blood and keep clots from forming, only a quarter of atrial fibrillation patients undergo the therapy. AHCPR researchers say 50 to 75 percent of all atrial fibrillation patients over 60 should receive this blood-thinning therapy.

AHCPR also has reported on carotid endarterectomy, a surgical procedure that removes fatty plaque from the arteries that carry blood from the heart to the brain. Because carotid artery blockage is a major cause of stroke, the surgery can be beneficial and cost-effective for patients with stroke-related symptoms and a high-degree of blockage. But AHCPR stresses that surgery benefits diminish when applied to patients without symptoms but with known blockages. Identifying blockages in asymptomatic patients can involve expensive and invasive diagnostic methods such as angiography, which carries its own risk of stroke and other complications. For that reason, AHCPR does not advocate large-scale screening of asymptomatic people.

Though stroke occurrence overall is on a slight upswing, there's reason to be hopeful. Medical professionals say it is unlikely that stroke will ever be eliminated completely. But medical weapons such as Activase and Coumadin hold promise to at least help curb the disorder's destructive path.

Heed Stroke's Warning Signs

From the onset of stroke symptoms, time is precious. Getting emergency help within three hours can mean the difference between severe brain damage and full or partial recovery.

If you have any of the following warning signs, call, or have someone call, 911 immediately:

• sudden weakness or numbness in the face, arm or leg
• sudden dimness or loss of vision, particularly in one eyev
• sudden difficulty speaking or understanding speech
• sudden severe headache with no known cause
• unexplained dizziness, unsteadiness, or sudden falls, especially in conjunction with the other warning signs.

Occasionally, strokes cause double vision, drowsiness, nausea, or vomiting. Also, because warning signs sometimes may last only a few minutes and disappear, it may be tempting to ignore them. But these "mini-strokes," or transient ischemic attacks (TIAs), could be your body's warning of a future full-blown stroke. So even if the symptoms go away quickly, seek medical help right away.

Control Stroke Risk Factors

The National Institute of Neurological Disorders and Stroke has identified five treatable risk factors associated with stroke. Agency officials emphasize that having a risk factor doesn't mean you'll have a stroke. And not having a risk factor doesn't mean you'll avoid a stroke. But your likelihood of having a stroke grows as the number and severity of risk factors increase. Risk factors that can be controlled by medical treatment include:

High blood pressure. This is by far the most important risk factor. Have your blood pressure checked by a qualified professional, and if it is high, seek medical attention to bring it into the normal range. Some over-the-counter (OTC) drugs may cause high blood pressure. For example, phenylpropanolamine (PPA), a widely used ingredient in OTC cough, cold, and weight-loss drugs, is under review because of concerns that the compound, especially in doses beyond those recommended, may elevate blood pressure and increase the risk of stroke. The Nonprescription Drug Manufacturers Association, at FDA's request, is sponsoring a study of PPA in OTC drugs and its possible relationship to an increased risk of stroke.

Cigarette smoking. Studies have linked smoking to the buildup of fatty substances in the carotid artery, the main neck artery supplying blood to the brain. Blockage of this artery is the main cause of strokes in Americans. Nicotine in cigarettes can raise blood pressure, and smoke can make blood thicker and more likely to clot.

Heart disease. Disorders such as coronary artery disease, valve defects, irregular heartbeat, and enlargement of one of the heart's chambers can create clots that may break loose and cause a stroke. Regular physicals will pinpoint treatable problems.

History of stroke. If you experience a "mini-stroke," or transient ischemic attack (TIA), with symptoms that quickly subside, seek emergency help. If you have had a stroke, consult with your doctor about what you can do to avoid a second stroke.

Diabetes. This causes destructive changes in blood vessels throughout the body, including the brain. If blood glucose levels are high at the time of a stroke, brain damage is usually more severe than when glucose is well controlled. Treating diabetes can delay complications that increase stroke risk.

About the Author

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